This proposal will attempt to determine whether a new non- invasive angiographic procedure utilizing MRI is efficacious in the diagnosis of atherosclerotic carotid artery disease. This objective will be achieved by comparing the accuracy of MRI angiograms to the accuracy of the next best imaging method (invasive angiography) and determining whether physicians will actually commit to a treatment choice following MRI. The authors of this proposal realize that if MRI projected angiography is to be accepted it must also be cost-effective. In order to facilitate analysis of the cost-effectiveness of MRI angiography, we will outline how our MR Center arrives at its cost and will also determine the cost in a free-standing MRI facility. Effectiveness will be modeled comprehensively using our determinations of accuracy, as well as analyses of the morbidity which is avoided with MRI angiography, the additional information that this technique is capable of acquiring, and patient preference.